// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_URL_REQUEST_REPORT_SENDER_H_
#define NET_URL_REQUEST_REPORT_SENDER_H_

#include <memory>
#include <set>
#include <string>

#include "base/callback.h"
#include "base/macros.h"
#include "net/http/transport_security_state.h"
#include "net/url_request/url_request.h"

class GURL;

namespace net {

class URLRequestContext;

// ReportSender asynchronously sends serialized reports to a URI.
// It takes serialized reports as a sequence of bytes so as to be agnostic to
// the format of the report being sent (JSON, protobuf, etc.) and the particular
// data that it contains. Multiple reports can be in-flight at once. This class
// owns inflight requests and cleans them up when necessary.
class NET_EXPORT ReportSender
    : public URLRequest::Delegate,
      public TransportSecurityState::ReportSenderInterface {
public:
    using ErrorCallback = base::Callback<void(const GURL&, int)>;

    // Represents whether or not to send cookies along with reports.
    enum CookiesPreference { SEND_COOKIES,
        DO_NOT_SEND_COOKIES };

    // Constructs a ReportSender that sends reports with the
    // given |request_context| and includes or excludes cookies based on
    // |cookies_preference|. |request_context| must outlive the
    // ReportSender.
    ReportSender(URLRequestContext* request_context,
        CookiesPreference cookies_preference);

    // Constructs a ReportSender that sends reports with the
    // given |request_context| and includes or excludes cookies based on
    // |cookies_preference|. |request_context| must outlive the
    // ReportSender. When sending a report results in an error,
    // |error_callback| is called with the report URI and net error as
    // arguments.
    ReportSender(URLRequestContext* request_context,
        CookiesPreference cookies_preference,
        const ErrorCallback& error_callback);

    ~ReportSender() override;

    // TransportSecurityState::ReportSenderInterface implementation.
    void Send(const GURL& report_uri, const std::string& report) override;
    void SetErrorCallback(const ErrorCallback& error_callback) override;

    // net::URLRequest::Delegate implementation.
    void OnResponseStarted(URLRequest* request) override;
    void OnReadCompleted(URLRequest* request, int bytes_read) override;

private:
    net::URLRequestContext* const request_context_;

    CookiesPreference cookies_preference_;

    // Owns the contained requests.
    std::set<URLRequest*> inflight_requests_;

    // Called when a sent report results in an error.
    ErrorCallback error_callback_;

    DISALLOW_COPY_AND_ASSIGN(ReportSender);
};

} // namespace net

#endif // NET_URL_REQUEST_REPORT_SENDER_H_
